Hand Tumors Flashcards
A 40-year-old man comes to the physician because of a 3-month history of pain and swelling over the proximal phalanx of the right index finger. He has no history of trauma. X-ray studies and MRI of the finger show an expansile osteolytic lesion of the proximal phalanx. Examination of a specimen obtained on biopsy confirms the diagnosis of giant cell tumor of the bone. Which of the following is the most appropriate staging test for this patient?
A) CT scan of the cervical spine
B) CT scan of the chest
C) MR arthrography of the wrist
D) MRI of the brain
E) Pulmonary function testing
The correct response is Option B.
This patient is presenting with a primary giant cell tumor of the proximal phalanx bone. Giant cell tumors of the bone are considered benign but locally aggressive tumors. Only 2 to 5% of giant cell tumors arise from the bones of the hand. These lesions have a 1 to 5% incidence of pulmonary metastases. The distal radius is the third most common site of giant cell bone tumor origin. Hand and distal radius tumors have higher rates of recurrence and metastasis. The lungs are the most common site of metastatic lesions and a CT scan of the chest is recommended as part of the diagnostic work-up.
The tumors are graded radiographically according to the Campanacci grading system. Grade I lesions are well-demarcated with an intact bony cortex. Grade II lesions show cortical expansion, and Grade III lesions show cortical destruction with soft-tissue extension. Grade I and II lesions can be treated with curettage and bone grafting. Adjuvant treatments such as phenol and liquid nitrogen have been recommended, but their efficacy has not been proven. Recurrence rates have been reported between 30 and 80% with this approach. Later stage tumors are treated with en bloc excision or amputation and reconstruction with vascularized or nonvascularized bone grafts. High rates of tumor recurrence are thought to be due to incomplete resection or late presentation at the time of diagnosis.
There is no specific added benefit for an arthrogram of the wrist in a tumor arising from the proximal phalanx as in this case. MR arthrography of the wrist, CT scan of the cervical spine, MRI of the brain, and pulmonary function testing are not typically used for staging giant cell tumor of the bone.
2018
A 24-year-old man who works as a laborer comes to the office because of a 2-cm mass on the dorsum of each hand. MRI shows an anomalous muscle. Which of the following is the most likely structure?
A) Extensor digitorum brevis
B) Extensor digitorum longus
C) Extensor digitorum brevis manus
D) Extensor indicis proprius
E) Extensor medii proprius
The correct response is Option C.
The extensor digitorum brevis manus is an anomalous muscle of the hand, which typically presents as a tender dorsal wrist mass. Incidence in the general population is estimated to be 2 to 3%. Anatomically, this muscle classically originates from the proximal dorsal radiocarpal ligament and inserts into the index finger extensor mechanism. Diagnosis is characteristic on ultrasonography or MRI. Treatment should be directed to symptoms and may include rest, activity modification, fourth dorsal compartment release, and/or muscle excision.
2018
A 72-year-old man is referred for surgical treatment of a 3-cm, tender red mass on the left elbow. It developed spontaneously over the past 3 weeks, and has not improved with 10 days of oral cephalexin therapy. During incision and drainage, the mass is found to be filled with copious milky white fluid with white solid granules. Pathology shows crystal deposits in the fluid. In addition to wound packing, which of the following is the most appropriate therapy?
A) Colchicine
B) Doxorubicin
C) Fluconazole
D) Methotrexate
E) Vancomycin
The correct response is Option A.
This patient has gout and presents with a gouty tophus of the elbow. The red nodule over a joint with milky white fluid is diagnostic. The treatment of choice is an anti-inflammatory agent, and colchicine is the most common. Gout results from an imbalance in purine metabolism, resulting in uric acid crystal deposition in the joints. The great toe is most commonly affected, classically known as podagra. When these nodules occur in the upper extremity, it is easy to misdiagnose them as bacterial in origin. For unknown reasons, gout is more common in men and occurs more frequently after surgery of any type.
Vancomycin would be appropriate for a severe, systemic bacterial infection such as methicillin-resistant Staphylococcus aureus (MRSA). In this case, purulent drainage would be expected, rather than the milky fluid with granules that was encountered.
Fluconazole is an antifungal. Methotrexate is used to treat rheumatoid arthritis, not gout. Doxorubicin is an antineoplastic chemotherapy agent and would be used to treat a biopsy-confirmed cancer.
2017
A 20-year-old man comes to the office because of an enlarging mass of the humerus. Examination of a specimen obtained on biopsy shows osteosarcoma. Which of the following locations is most likely metastatic in this patient?
A) Brain
B) Colon
C) Digit
D) Liver
E) Lung
The correct response is Option E.
The most common site of osteosarcoma metastasis is the lung. The tumor is most commonly found in the upper extremity proximal humerus. Osteosarcoma is the most common malignant bone tumor. It is most commonly found in childhood and rarely in the hands at that time. The incidence in the hand is 0.18%. In patients over 40 years of age, the proximal phalanx and metacarpals are involved.
Symptoms often begin 3 to 12 months prior to diagnosis and include pain and swelling. Radiographs show a sunburst pattern with periosteal elevation at Codman’s triangle. Treatment includes wide excision or amputation and neoadjuvant chemotherapy.
Malignant tumors of bone are rare, occurring in 1/5000 tumors.
2017
A 25-year-old postpartum woman comes to the office because of a painful mass of the left little finger. The patient reports that the swelling began during her teen years but enlarged rapidly and became painful during the third trimester of her recent pregnancy. Physical examination shows the mass is soft and compressible. The patient reports that the mass becomes firm if the hand is dependent. Which of the following is the most appropriate method of treatment in this patient?
A) Arterial embolization
B) Oral propranolol therapy
C) Pulsed-dye laser therapy
D) Surgical excision
E) Observation
The correct response is Option D.
In this patient, observation would be inappropriate. Small, painless lesions can be safely observed, but symptoms such as pain or loss of function warrant intervention. In this patient, who has a painful venous malformation, observation would be inappropriate. Pulsed-dye laser therapy provides effective treatment for cutaneous vascular lesions. Although the image does show a bluish discoloration over the lesion in the small finger, the skin is largely uninvolved. This venous vascular malformation represents a deeper lesion that would be unaffected by laser therapies directed at the skin. Surgical excision remains the mainstay for treatment of symptomatic low-flow vascular malformations such as this one. The patient description presents a classic picture (soft, compressible, swelling with dependency, rapid growth with hormonal changes). Sclerotherapy may be combined with surgical excision for larger or more diffuse lesions. In this patient, the small, localized lesion can be approached by surgical excision alone. Arterial embolization can decrease the size of high-flow vascular malformations and decrease blood loss during surgical excision. The presentation of this lesion is most consistent with a low-flow, venous malformation (soft, compressible, swelling with dependency). As there is no arterial feeding vessel, this lesion would not be amenable to arterial embolization. Propranolol would be appropriate treatment for infantile hemangioma but is not appropriate for venous malformation.
2017
An otherwise healthy 30-year-old man is brought to the office because of a slow-growing mass on the volar base of the left ring finger. There is no history of trauma. The patient reports no pain or discomfort. Examination shows a 1.0-cm midline mass that is located immediately distal to the metacarpophalangeal flexion crease. The mass is firm, nonpulsatile, and does not transilluminate. The mass does not move with finger flexion or extension. X-ray study shows no abnormalities. Which of the following is the most likely diagnosis?
A) Digital lipoma
B) Fibrosarcoma
C) Ganglion cyst
D) Giant cell tumor of tendon sheath
E) Neurilemmoma
The correct response is Option D.
The clinical scenario describes a lesion that is midline and overlies the flexor tendon sheath. The two most likely diagnoses in this scenario are ganglion cyst and giant cell tumor of tendon sheath. Both of these lesions tend to present as a ball-like lesion as described. These entities are usually distinguished on the basis of a transillumination test: light will pass through the mass if it is a ganglion cyst (since it is fluid) and will not if it is a giant cell tumor (or other solid masses). Since light was not transmitted through this lesion, and given the characteristic and location of the lesion, it is most likely to be a giant cell tumor of tendon sheath. Fibrosarcoma is extremely unlikely and would almost never present as a midline spherical mass on the palmar surface of the finger. Neurilemmoma is a relatively rare neural tumor that arises from the nerve sheath; on the volar aspect of the finger, it would present more laterally in the path of the digital nerve. Digital lipoma can appear as a midline mass, but this entity is very uncommon.
2017
A 44-year-old, right-hand–dominant man comes to the office because of a painless deep mass on the dorsum of the dominant hand. Biopsy shows myxoinflammatory fibroblastic sarcoma. Which of the following factors is most associated with the need for flap coverage and local recurrence?
A) Digital involvement
B) Dorsal versus palmar location
C) Patient age
D) Transverse biopsy incision
E) Treatment with radiation therapy
The correct response is Option D.
Sarcomas are rare tumors in the hand. The dorsum and mid palm are most commonly involved. Tumor types are most commonly epithelioid, malignant fibrous histiocytoma, and synovial sarcoma. The performance of a “suboptimal” biopsy incision (using a site or incision that cannot be incorporated into a standard limb salvage incision or amputation flap) is predictive of the need for flap reconstruction and local recurrence. The other factors listed may encourage a plastic surgeon to consider flap coverage but are not predictive in large series. A transverse incision in the extremities is considered “suboptimal.”
The importance of this knowledge is that surgeons must carefully consider the placement of incisions and the use of inadequate excisions when approaching unknown hand masses.
2017
A 63-year-old woman comes to the office because of progressive pain of the right ring finger over the past 4 months. Physical examination shows the ring finger is held in a flexed position with the metacarpophalangeal and proximal interphalangeal joints each at a 45-degree angle. Tenderness over the palm with active digital flexion is noted. The patient reports that when she wakes in the morning, the ring finger is generally fixed in a flexed position, and she has to physically straighten the finger with her other hand. Over the past month, the finger has remained flexed. Medical history includes type 2 diabetes mellitus and hypertension. Which of the following is the most likely diagnosis in this patient?
A) Central slip rupture
B) de Quervain tendinitis
C) Digital stenosing tenosynovitis
D) Dupuytren contracture
E) Ulnar nerve compression at the elbow
The correct response is Option C.
Stenosing tenosynovitis, or trigger finger, is an inflammatory tendinopathy of the digital flexor tendons. It can present with pain, stiffness, and occasionally a mass in the palm. Long-standing stenosing tenosynovitis may occasionally lead to a flexion contracture of the finger after proper treatment is not performing. Dupuytren disease is a flexion contracture of the digits and palm due to contracture of the palmar fascia. Dupuytren disease is a progressive condition and the patient would not be able to passively extend her finger. de Quervain tenosynovitis is a tendinitis affecting the tendons of the first dorsal compartment resulting in pain over the dorsal wrist and thumb. Ulnar nerve compression at the elbow may affect the intrinsic muscles causing a claw deformity and contracture of the ring finger. Commonly, the little finger is also affected, and the patient would have symptoms of paresthesia or numbness in the ulnar innervated fingers. Central slip rupture would cause a Boutonnière deformity with flexion at the PIP and hyperextension at the DIP.
2017
A 35-year-old man comes to the office because of a painless enlargement of the right index finger for the past 6 months. An x-ray study is shown. Curettage of the lesion and grafting with demineralized bone matrix are planned. Which of the following is the most likely outcome of this procedure in this patient?
A) Distant metastasis
B) Local recurrence of the lesion within 2 years
C) Pathologic fracture and extension to surrounding soft tissue
D) Regional nodal metastasis
E) Uneventful healing without recurrence
The correct response is Option E.
Uneventful healing without recurrence is most likely in this patient. The bone lesion pictured in the x-ray is characteristic of an enchondroma. Enchondromas are benign chondrogenic tumors arising from aberrant cartilaginous foci within the medullary canal. Chondroblasts are thought to escape from the physis and proliferate in the metaphysis.
Enchondromas are the most common bone tumor found in the hand (approximately 90%). They are found mostly in the proximal phalanx, middle phalanx, and metacarpal. Enchondromas are benign, expansile, and locally destructive lesions. They are usually asymptomatic and discovered incidentally on radiographs taken for another reason. Pain is more frequently associated with a malignant tumor such as a chondrosarcoma or a pathologic fracture from cortical thinning. Typical radiographic features are a well-circumscribed, radiolucent lesion that may be expansile or purely lytic with popcorn stippled calcification.
Smaller asymptomatic lesions can be observed. Larger lesions that are potentially unstable or symptomatic are treated by curettage with or without bone grafting. Many authors recommend the addition of autologous or allograft bone following tumor excision. However, there are studies showing no benefit to adding bone graft or bone graft substitute. There is no consensus on the treatment of lesions involving a pathologic fracture. Stable fractures should be treated with immobilization and allowed to heal prior to treating the enchondroma secondarily. Unstable fractures can be safely treated with curettage and fracture fixation in a single stage.
Enchondromas are benign and complete resection is curative. Recurrence of a lesion after surgery may suggest that the lesion is actually a low-grade sarcoma. The risk of malignant transformation in a solitary enchondroma is approximately 1%.
Pathologic fractures are relatively common, especially in the hand. These occur with minor trauma when the lesion has resulted in significant cortical thinning but expansion of the tumor into the surrounding soft tissue does not occur.
The potential for malignant transformation is greatly increased in multiple enchondromatosis, such as Ollier disease and Mafucci syndrome. Ollier disease is a nonhereditary form of multiple enchondromatosis associated with skeletal dysplasia. Mafucci syndrome is characterized by multiple enchondromatosis and cutaneous hemangiomas. The risk of malignant transformation to chondrosarcoma or osteosarcoma in these cases is up to 30%. Low-grade chondrosarcomas have a low metastatic potential.
2017
A 44-year-old man comes to the office because of a palpable mass of the right dorsoradial distal forearm. The patient reports that the mass has been growing slowly over the past 2 years. On examination, the mass is nontender. Excisional biopsy shows the mass is well encapsulated and separates easily from within the fibers of the dorsoradial sensory nerve, as the nerve emerges from beneath the brachioradialis tendon. Which of the following cells is the most likely origin of this mass?
A) Adipose
B) Giant
C) Glial
D) Spindle
E) Tendon
The correct response is Option C.
The mass is most consistent with a neurilemmoma or Schwann cell tumor. These are benign, encapsulated tumors of the nerve sheath. Their cells of origin are glial, likely Schwann cells. These masses usually arise from the side of or from within the nerve. Symptoms can be vague and manifest as a dull ache or as symptoms consistent with nerve compression.
A lipoma derives from adipose cells, but these generally do not originate from the substance of the nerve. Tumors consisting of tenocytes are essentially unheard of, but giant cell tumors originate from the tendon sheath and are usually intimately involved with the tendon sheath and thus unlikely to be found within the fibers of a nerve.
Pathology of spindle cells which form muscle, are usually seen in the setting of sarcoma or carcinoma. In general, they are usually found in a subcutaneous, peritendinous, and intramuscular plane. They are taken with margins and are unlikely to shell cleanly out of their soft tissue of origin.
2017
A 34-year-old woman comes for evaluation because of a 4-month history of pain in the fingers of the right hand. The pain is most severe in the ring finger and is exacerbated by exposure to cold temperatures. Physical examination shows a blue discoloration under the nail of the ring finger. Which of the following is the most likely diagnosis?
A) Cutaneous melanoma
B) Epidermal inclusion cyst
C) Giant cell tumor
D) Glomus tumor
E) Mucous cyst
The correct response is Option D.
Glomus tumors are benign neurovascular tumors. The glomus apparatus is believed to function as a thermoregulatory control mechanism. Glomus tumors generally are found in the hand, most commonly in the digit, and often in the fingertip. They are characterized by severe pain, especially with exposure to cold temperatures. Cold sensitivity can be evoked by placing the digit in an ice bath. Glomus tumors are well visualized on MRI using T-1 and T-2 weighted images. Ultrasonography may also be useful in identifying glomus tumors. Treatment for glomus tumors is complete surgical excision. Up to 25% of these tumors may have multiple lesions.
Malignant melanomas may be seen in the subungual area. These tumors usually are identified by a pigmented streak under the fingernail. These tumors are generally painless and often go unrecognized. A pigmented lesion under the nail should be biopsied if it does not resolve by 4 weeks.
Giant cell tumors are benign soft-tissue tumors. They are the second most common tumor in the hand. These tumors generally occur on the volar surface of the fingers and hand. They present as a firm, nodular, nontender mass.
Epidermal inclusion cysts are benign masses of the hand thought to be the result of implantation of the epithelial cells into the underlying soft tissue. They produce a painless mass. Treatment of these cysts is by marginal excision.
A mucous cyst is a term used to describe a ganglion cyst of the distal interphalangeal (DIP) joint. This is a misnomer because the cysts are not filled with a mucous material, but synovial fluid. The cyst may produce nail deformities. Pain may be associated with these cysts, and is caused by the underlying arthritis of the DIP joint.
2016
A 30-year-old woman comes to the office for consultation regarding a 2-year history of a slow-growing mass on the volar aspect of the left ring finger. The growth is adjacent to the distal interphalangeal (DIP) joint. Physical examination shows the mass is firm and cannot be transilluminated. The overlying skin is intact. Which of the following is the most likely diagnosis?
A) Desmoid tumor
B) Ganglion cyst
C) Giant cell tumor
D) Pyogenic granuloma
E) Vascular tumor
The correct response is Option C.
The mass described in this scenario is a giant cell tumor of the tendon sheath. These growths are common in adults younger than 50 years of age. These masses are slow-growing, firm, lobulated, and painless. Giant cell tumors are the second most common tumor of the hand, after ganglion cysts. Unlike ganglion cysts, giant cell tumors cannot be transilluminated. Moreover, they usually occur on the volar aspect of the hand, and bone invasion is not commonly seen. These characteristics are not true of vascular tumors, desmoids, or pyogenic granulomas.
2015
A 48-year-old right-hand–dominant man comes to the office for evaluation of a tender mass of the distal volar forearm. Tinel sign is positive at the site of the mass. MRI shows that the mass involves the median nerve. Biopsy of the mass confirms a malignant peripheral nerve sheath tumor. On the basis of these findings, this diagnosis is most likely associated with which of the following conditions?
A) Amyotrophic lateral sclerosis
B) Charcot-Marie-Tooth disease
C) Multiple sclerosis
D) Neurofibromatosis 1
E) Parkinson disease
The correct response is Option D.
The correct response is that neurofibromatosis 1 (NF1) is associated with malignant peripheral nerve sheath tumors (PNSTs).
The majority of “nerve tumors” are PNSTs. Schwannomas and neurofibromas are the most common.
Malignant soft-tissue tumors of the hand are very rare and constitute only 1 to 2% of hand tumors. Malignant PNSTs have a very low annual incidence of 0.001% in the general population, and between 2 and 5% in patients with NF1. The plexiform subtype of neurofibromas poses a substantial risk of malignant degeneration.
Amyotrophic lateral sclerosis, multiple sclerosis, Charcot-Marie-Tooth disease, and Parkinson disease are not commonly associated with malignant PNSTs.
2015
A 25-year-old man is evaluated because of a deep 6-cm, palpable mass to the mid-volar forearm. MRI is performed, but the diagnosis remains inconclusive. An initial diagnostic biopsy is planned. Which of the following is most appropriate during this procedure?
A) Avoidance of cautery
B) Leaving the biopsy site open with compressive dressings
C) Performance of an excisional biopsy
D) Placement of a skin crease transverse incision
E) Use of a tourniquet without Esmarch bandage
The correct response is Option E.
An open biopsy is done for forearm tumors that cannot be diagnosed as benign on clinical or radiographic grounds. For a large lesion, an incisional biopsy is performed to minimize the risk of surrounding surgical field tumor contamination. Wide undermining must be avoided.
The biopsy is done with a bloodless field and a tourniquet, but elevate the arm only for exsanguination without an Esmarch bandage. Obtain meticulous hemostasis before wound closure. Sutures are placed close to the wound edges to avoid additional tumor skin contamination.
While a transverse incision may provide a better cosmetic result, it may complicate limb-sparing surgery if pathology determines malignancy.
2015
A 7-year-old girl is brought for evaluation because of a 2-month history of an asymptomatic 1-cm mass over the volar radial aspect of the wrist. The parents note no history of trauma. On physical examination, the mass is not adherent to the skin but affixed to the deeper tissues. She has full range of motion of the wrist without signs of carpal instability. X-ray studies of the wrist show no abnormalities. MRI is consistent with a ganglion. There is no evidence of carpal ligamentous injury. Which of the following is the most appropriate next step in management?
A) Observation
B) Sclerotherapy
C) Closed rupture
D) Wrist arthroscopy
E) Surgical excision
The correct response is Option A.
The next step in management is a period of observation. Although there is no general consensus regarding the best treatment for pediatric ganglions, most prefer observation and splinting for asymptomatic wrist ganglions. In the literature, the majority of pediatric wrist ganglions will spontaneously rupture and resolve without intervention. The diagnosis of volar wrist ganglion has been made by history, physical examination, and MRI, making needle biopsy unnecessary. This mass is asymptomatic and there is no sign of carpal ligamentous injury on the x-ray study or MRI, therefore there is no surgical indication for excision or wrist arthroscopy.
Closed rupture is a trauma and antiquated therapy for ganglions. Sclerotherapy does not treat wrist ganglia.
2015
A 48-year-old woman comes for evaluation because of a 6-month history of an increasing mass on the right ring finger. She reports that a similar mass was removed from this location 2 years ago. Medical records show that the mass was solid and of a variegated tan-brown color. The pathology report identified foamy histiocytes and hemosiderin deposits. Physical examination today shows a firm, well-demarcated mass on the dorsal-ulnar aspect of the ring finger proximal phalanx. Skin is not adherent to the mass. A photograph is shown. This patient is at increased risk for which of the following?
A) Compromise of blood flow to the finger
B) Invasion of the underlying bone
C) Local recurrence or extension
D) Metastasis to the liver
E) Spread to the regional lymph nodes
The correct response is Option C.
This is a giant cell tumor of the tendon sheath.
Ganglion cysts are the most common tumor of the hand, but are cystic in character. Giant cell tumor of the tendon sheath (also called localized nodular synovitis, fibrous xanthoma, and pigmented villonodular tenosynovitis) is the second most common tumor, but it is the most common solid tumor affecting the hand. The hemosiderin deposits give the tumor its variable tan-brown appearance.
This tumor is noted to recur locally, particularly if incompletely excised. Giant cell tumors are not known to metastasize either distantly or to regional lymphatics. Whereas giant cell tumor of bone involves the bone itself, giant cell tumor of tendon sheath does not. This tumor is not known to invade or compromise the digital vessels and thus would not compromise blood flow to the digit.
2014
A 62-year-old woman presents because of a 6-month history of a painless mass near the nail fold of the left index finger. The patient reports that clear thick drainage leaks intermittently from the nail fold. She is concerned about the appearance of the nail. A photograph is shown. On evaluation of this patient, which of the following additional studies in her workup is most appropriate?
A) Blood work
B) Culture of a drainage specimen from the nail fold
C) Diagnostic x-ray study of the finger
D) Incisional biopsy of the mass
E) MRI of the finger
The correct response is Option C.
This is a mucous cyst based on history and examination. Mucous cysts are cysts that arise from the distal interphalangeal joints. They are frequently associated with dorsal osteophytes secondary to osteoarthritis and x-ray studies are useful to establish the severity of osteophytes. X-ray views usually demonstrate osteophytes in proximity to the cyst. The cyst can decompress and clear viscous fluid can be seen. Pressure on the germinal matrix from an enlarging mucous cyst can cause nail grooving, which this patient demonstrates.
These masses are benign and do not require treatment. Aspiration and corticosteroid injection can be considered for nonsurgical treatment. The osteophyte is thought to be an inciting cause of the mucous cyst in these patients and should be removed when surgically treating these patients hence the utility of x-rays in evaluation of the patient. The cyst and stalk are traditionally removed as well.
MRI is unnecessary as clinical examination should be sufficient to establish the diagnosis.
Blood work and culture would be unable to establish a diagnosis.
Culture is sometimes necessary if there are signs of infection but there are no concerning signs or symptoms in this patient. Biopsy is helpful when clinical diagnosis is suspect, but unnecessary with this benign mass.
X-ray studies of this patient’s left hand (anteroposterior and lateral) are shown.
2019
A 17-year-old boy presents with a mass of the left forearm that has been enlarging over the past 3 months. A photograph is shown. Biopsy of the mass is consistent with spindle cell sarcoma. MRI shows a well-encapsulated mass that does not infiltrate neurovascular structures. CT scan of the chest shows no evidence of metastatic lesions. Which of the following is the most appropriate next step in management?
A) Amputation at the midforearm
B) Chemotherapy only
C) Excision and chemotherapy
D) Excision and radiation therapy
E) Radiation therapy only
The correct response is Option D.
Soft tissue sarcomas are rare malignant tumors representing less than 1% of all malignancies, with only 25% occurring in the upper extremity. The diagnostic workup generally includes a biopsy, magnetic resonance imaging scan to assess the extent of the tumor and its relationship to adjacent structures, and a computed tomography scan of the chest. This combination allows for appropriate clinical staging of the patient. The role of sentinel lymph node biopsy in the workup of soft tissue sarcomas is controversial. Treatment consists of wide excision, primary reconstruction, and radiation therapy (adjuvant or neoadjuvant). The tumor must be completely removed with a cuff of normal tissue (at least 1 cm); violation of the tumor decreases 5-year survival from 87 to 47%. More than 90% of extremity sarcomas can be managed with a limb-sparing resection.
Chemotherapy is rarely indicated and is never used as the only treatment for soft tissue sarcoma. Primary amputation is considered when the tumor infiltrates major neurovascular structures and resection would result in the sacrifice of more than one major peripheral nerve. Additional indications for amputation include involvement of the interosseous membrane, advanced disease with extensive loss of functional tissues, and severe comorbidities limiting reconstructive options.
2020
A 66-year-old man presents with a mass along the ulnar margin of the index finger proximal phalanx. The patient reports that over the past year, the mass has grown in size. Physical examination shows the mass is now interfering with digital flexion. X-ray studies show bony erosion into the cortex of the middle phalanx. Excisional biopsy demonstrates a tan, multilobulated mass that has surrounded the digital nerve and invaded the bone cortex. Which of the following is the most likely diagnosis in this patient?
A) Chondrosarcoma
B) Epidermal inclusion cyst
C) Giant cell tumor of tendon sheath
D) Retinacular cyst
E) Schwannoma
The correct response is Option C.
Giant cell tumors of the tendon sheath are the second most common hand masses. They are slow-growing and painless, and affect the volar surfaces of the index, middle and ring finger, at the PIP or DIP joints. They usually appear tan or yellow, lobulated, and well-circumscribed. Bony erosion secondary to long-standing pressure may be observed on x-ray studies. Treatment is excision, with recurrence rates ranging from 0 to 44 percent. High recurrence rates are associated with satellite lesions, poor encapsulation, distal locations, intraosseous involvement, concurrent degenerative joint disease, or involvement of the adjacent joint/tendon. Radiotherapy following surgical excision has shown recurrence rates as low as 4 percent.
Schwannomas are benign peripheral nerve tumors derived from Schwann cells, that can involve the nerves of the hand. They are well encapsulated and slow growing, and typically arise over flexor surfaces. They present as a soft, nontender mass that is mobile and may cause associated paresthesias. Magnetic resonance imaging may be helpful to evaluate for malignant characteristics. These tumors can often be shelled out because they involve the nerve sheath instead of individual fascicles, with little risk of postoperative neurologic deficits. Malignant transformation is rare. Epidermal inclusion cysts are painless, firm, keratin-filled cysts developing from traumatic implantation of epithelium into the subcutaneous tissue. Typical locations include the volar palm and digits. No risk of malignant transformation has been reported, but cortical destruction can be observed, raising suspicion for a neoplastic process. There is a low rate of recurrence with surgical excision. These masses can be differentiated from giant cell tumors of the tendon sheath, in that they are cystic structures filled with keratin and not mutilobulated, solid masses.
Ganglions are usually solitary and occur in specific locations in the hand and wrist. The most common ganglion locations are the dorsal and volar wrist regions. They also occur in the digital flexor tendon sheath (retinacular cyst), arising from the A1 pulley. There is no consensus regarding the preferred treatment of a flexor tendon sheath ganglion. Historically, the large number of therapeutic options described suggests that a predictable treatment approach could not be agreed upon. Recent literature indicates that there are two acceptable treatment options: cyst aspiration or surgical excision.
Chondrosarcomas are the most common primary malignant bone tumors of the hand, most frequently affecting the proximal phalanx. They may arise de novo or from malignant transformation of benign cartilaginous lesions such as enchondromas. At imaging, it may often be difficult to distinguish chondrosarcomas from their benign chondroid counterparts such as enchondromas. Phalangeal chondrosarcomas are locally aggressive and, unlike chondrosarcomas of other skeletal structures, rarely metastasize.
Cortical breakthrough, irregular cortical thickening, and a soft-tissue component are all suggestive of chondrosarcoma rather than benign tumors such as enchondroma. Recurrence rates with intralesional excision are historically high, such that wide excision or amputation had previously been the mainstay of surgical treatment. Recent literature, however, advocates intralesional excision with close follow-up for low-grade lesions or phalangeal tumors in circumstances where amputation will result in significant functional loss. No role for irradiation or chemotherapy has been described.
2020
A 13-year-old girl presents with an enlarging mass on the right hand. The patient’s mother reports that the child has always had a bruised-appearing birthmark on the hand, but the region started enlarging in the last year. The patient reports aching pain mainly associated with exercise. On examination, the mass increases in size with dependence. A photograph, an x-ray study, and MRI images are shown. Which of the following is the most likely diagnosis?
A) Arteriovenous malformation
B) Hemangioma
C) Lymphatic malformation
D) Port-wine stain
E) Venous malformation
The correct response is Option E.
Vascular anomalies are divided into tumors and malformations. Hemangiomas are a classic example of a vascular tumor. Malformations are present at birth and grow with age. Vascular malformations don’t regress with age. They may not be obvious at a young age and become more evident as the patient ages or goes through hormonal changes such as puberty and pregnancy (if female). Other reasons for enlargement include trauma, infection, and thrombosis. Vascular malformations are secondary to an error in the morphogenesis of blood vessels, and they don’t enlarge secondary to cellular hyperplasia. There is a normal rate of endothelial cell turnover.
Vascular malformations are characterized by rate of flow and type of predominant tissue in the malformation. Slow-flow vascular malformations include capillary malformations, venous malformations (VMs), and lymphatic malformations (LMs). Fast-flow vascular malformations include arteriovenous malformations (AVMs) or fistulas. Combined vascular malformations aren’t uncommon. Most vascular anomalies can be diagnosed by history and clinical examination. However, medical imaging has become an important component for diagnosis and treatment planning.
This patient presents with a vascular malformation based on history, examination, and MRI. The subtype for this patient is consistent with a venous malformation based on findings of phleboliths (blood clots that become hardened and calcified) on MRI and x-ray. VMs are the most common type of vascular malformation. These malformations may be present in all tissue planes but, when present at the subcutaneous level, give the skin a purplish hue that is accentuated with gravity position of the limb. VMs are traditionally compressible, and the purplish hue and fullness of the mass will frequently diminish with limb elevation against gravity. Painful clots and phleboliths are commonly identified and may be sources of pain causing acute presentation. Patients may report chronic aching pain, swelling, and stiffness that is worse in the morning. Phleboliths demonstrated on imaging are pathognomonic for VMs. VMs of the extremity can be associated with undergrowth or overgrowth.
Ultrasonography, MRI, and catheter angiography are frequently used imaging studies to delineate the rate of flow, identify features, and evaluate the extent of malformation. X-ray study or CT scan may be used to assess bony involvement/bony deformation and may show phleboliths appearing as rounded, lamellated calcifications. Ultrasonography with Doppler scan is frequently the first-line imaging study; it can assess the rate of flow (delineate fast/slow flow), depth of the mass, and any feeding vessels. Compressibility of the mass can also be assessed. An ultrasound of a VM usually shows a sponge-like collection of vessels and compression; then release will show inflow of blood into the cavity. Phleboliths, ectatic/dilated vessels, and thickened overlying tissue can all be shown on ultrasonography. MRI of VMs show multilocular, lobulated, septated masses. These are hypo/isointense on T1-weighted sequences and hyperintense on T2 sequences. VMs can be shown to involve nerves, tendons, muscles, joints, and adjacent organs. Phleboliths can also be appreciated on MRI as low-signal regions/flow voids.
The other options wouldn’t be the most correct diagnosis for this patient. Hemangioma would be present at birth and grow rapidly (and regress for an involuting hemangioma). An AVM is a high-flow lesion and wouldn’t have phleboliths on imaging. An LM is a low-flow lesion and similarly wouldn’t demonstrate phleboliths. Neither an AVM nor an LM would appear to have increased size/congestion with dependence. Port-wine stain or capillary malformation is a flat macular cutaneous malformation and wouldn’t be characterized by this patient’s findings or imaging.
2022
A 33-year-old man presents with a 2-year history of a 4-mm reddish discoloration underneath the left index fingernail. He reports significant tenderness to pressure directly on the discoloration, but not the surrounding tissue, along with pain in the area that is worse when going outside in the winter and reaching for items in the freezer. A photograph is shown. Which of the following is the most likely etiologic factor in the origin of this patient’s mass?
A) Arthritis at the distal interphalangeal joint
B) Capillary malformation
C) Growth of myoarterial unit
D) Proliferation at the germinal matrix
E) Trauma to the nail bed
The correct response is Option C.
The most likely etiologic factor involved in the origin of this mass is growth of myoarterial unit.
This patient has evidence of a glomus tumor, which is a rare benign tumor that often presents in the subungual region. Glomus tumors arise from the glomus body, which is a myoarterial unit that functions in thermoregulation. Clinical findings include focal tenderness and cold intolerance.
Some tests for glomus tumor include the Love pin test, Hildreth test, and cold-sensitivity test. In the Love pin test, pressure is applied to the area with a pinhead and the area containing the glomus tumor becomes exquisitely painful. In the Hildreth test, pain in the area is relieved by the use of a tourniquet, due to the restricted blood supply. In the cold-sensitivity test, cold water or an ice cube elicits increased pain in the affected area.
Diagnosis of glomus tumor can be verified with MRI or ultrasonography. Management consists of surgical excision of the lesion, as shown in the photograph.
Arthritis at the distal interphalangeal joint can give rise to digital mucous cysts, which can demonstrate nail deformity but typically are not painful.
Capillary malformation can result in reddish-appearing vascular tumors, but these would not typically present the sensitivity and cold intolerance seen in glomus tumors.
Proliferation at the germinal matrix can give rise to nail abnormalities, but these typically manifest as abnormalities in the nail plate rather than in the subungual region (i.e., melanonychia, skin cancers).
Trauma to the nail bed can result in subungual hematoma, which can cause pain, but a hematoma typically will resolve and not persist for years.
2022
